the present invention relates to a voice information service system wherein voice information recorded in the system is reproduced to be served to a user through a telephone network according to selection of the user, and particularly relates to an operation method for selecting an item of the voice information to be served.
In conventional voice information service systems, a different information number is assigned to each item of voice information prepared in the systems, so that a user can designate a desired information number by way of a DTMF (dual Tone Multi-Frequency) code by pushing numeral keys of a telephone, directly or according to a guidance, for obtaining necessary information.
As a prior art of application of the DTMF code, there is a communication system disclosed in a Japanese utility model application laid open as a provisional Publication No. 90357/88. In this prior art, one of various functions of the communication system, which is provided with telephone keys, is selected by pushing a sequence of the telephone keys including an asterisk key, sharp key and ten keys.
However, both in the conventional voice information systems and in the above prior art, the user's designation is discriminated only with the DTMF code itself, that is, only according to kinds and order of telephone keys manipulated by the user.
Therefore, for entering a desired DTMD code, it is necessary for the user to push an intending key or keys in correct order by selecting them among the telephone keys. this is inconvenient for a cordless telephone such as a mobile phone which is in widespread use.
In order to enter a DTMF code by way of the cordless telephone, wherein the telephone keys are unitized in a handset, the user is forced to put the handset away from his ear for selecting the intended keys to be pushed, and again to put the handset to his ear for receiving the voice information. Furthermore, this "off-ear" handset manipulation may be forced several times, especially when the necessary voice information is to be selected by entering the DTMF codes in accordance with a guidance, resulting in mis-receiving of the voice information.